Hormones and Endocrinology Flashcards
Which hormones cross the membrane and which don’t?
Lipid soluble can cross
Water soluble require receptors to cross
Definition of hormones
Chemical messenger molecules that circulate in the blood and act on target cells
What is the difference between the endocrine, paracrine and autocrine response?
Endocrine - wen target cell is some distance away from the secretory cells
Pracrine- Target cell close/adjacent to secretory cell
Autocrine - released, hits target cell then loops back and binds to secretory cell to have negative feedback
Give examples of small chemicals/modifies amino acids
Dopamine
Adrenaline
Give examples of protein hormones
Oxytocin ADH Growth Hormone (somatotropin) Prolactin FSH TSH Insulin
Where are oxytocin and ADH produced?
Posterior pituitary
Where are Growth Hormone and Prolactin produced?
Anterior pituitary
What is the role of Growth Hormone?
Stimulates growth, cell division and regeneration
A mitogen - specific to certain types of cells
What is Prolactin?
198 residue protein (23kDa)
Closely related to GH and Placental Lactogen (PL) with properties and functions resembling both a hormone and cytokine
Where are FSH and TSH produced?
Anterior Pituitary
FSH and TSH are hetero-dimeric, what does this mean
Both parts bind to the receptor
Why can’t proteins be given by the oral route?
What other routes can be used?
Proteins get digested
Injection
Aerosols
Depot formulations
Which hormones are derived from Tyrosine?
Dopamine Noradrenaline Adrenaline T3 T4
Which hormones are derived from Tryptophan?
Melatonin
(derived from dietary tryptophan VIA serotonin
Where is serotonin converted to Melatonin?
Pineal Gland
What is structurally similar in steroid hormones?
All have teh same basic C17, 4 ring structure
Give examples of steroid hormones (lipid derived) and their C number
Oestradiol C18
Testosterone C19
Progesterone C21
Cortisol C21
What can aromatase (Anastazole) inhibitors be used for?
Patients with breast cancer (where tumour is oestrogen recpetor positive)
What are the two types of endocrine organs?
Primary - function is the secretion of hormones
Secondary - non-endocrine function
Where are the hypothalamus, pituitary and pineal glands?
Hypothalamus: below the thalamus, above the brain stem
Pituitary: in a small bone cavity below the hypothalamus
Pineal gland: epithalamus, between 2 hemispheres in the centre of the brain
Where are the hypothalamus, pituitary and pineal glands?
Hypothalamus: below the thalamus, above the brain stem
Pituitary: in a small bone cavity below the hypothalamus (sella turcica)
Pineal gland: epithalamus, between 2 hemispheres in the centre of the brain
What kind of hormones does the pineal gland produce?
Melatonin - helps regulate circadian rhythm
Where are the Thyroid and Parathyroid glands?
Neck region just beow the larynx
Sitting above and around the trachea
What does the thyroid gland produce and what do these do?
Produces T3 and T4
These help regulate metabolism
Produces calcitinin
This regilates production of calcium